The development of mechanical electrical, chemical and biological devices and systems that include or comprise nanoscale components, sometimes termed nanotechnology, has been slowed by the unavailability of or limitations inherent in devices that enable sensing, measuring, analyzing, and modifying objects with nanometer resolution and sensing, measuring, analyzing, moving, manipulating, fabricating and modifying objects with nanometer dimensions.
One class of devices that have found some use in nanotechnology applications are proximity probes of various types including those used in scanning tunneling microscopes (STM), atomic force microscopes (AFM) and magnetic force microscopes (MFM). While good progress has been made in controlling the position of the macroscopic probe to sub-angstrom accuracy and in designing sensitive detection schemes, the tip designs to date have a number of problems.
One such problem arises from changes in the properties of the tip as atoms move about on the tip, or as the tip acquires an atom or molecule from the object being imaged. Another difficulty with existing probe microscope tips is that they typically are pyramidal in shape, and that they are not able to penetrate into small “holes” on the object being imaged, and they may give false image information around sharp vertical discontinuities (e.g., steps) in the object being imaged, because the active portion of the “tip” may shift from the bottom atom to an atom on the tip's side. Moreover, conducting conventional probe microscope tips have never been successfully covered with an insulating material so that the only electrically-active element is the point of the tip itself.
Conventional probe microscope tips also are very rigid in comparison to many of the objects to be examined, and with “soft” samples (e.g., biomolecules like DNA) conventional AFM tips misrepresent the thickness of the object imaged, because that object is literally compressed by the action of the tip.
Thus, there is a need for macroscopically manipulable nanoscale devices for observing, fabricating or otherwise manipulating individual objects in a nanoscale environment that address the foregoing and other disadvantages of the prior art.